The very first thing you might notice when looking through this manga's page would be the 'ecchi' and 'harem' tags, which would make half of you give up on the spot, while the other half would already be reading the manga instead of this review. This review is primarily aimed at the former half, the group that is less than enthralled by stereotypical ecchi/harem fare.

Story (6/10):
The story of Yuragi sou no Yuuna san is pretty straightforward - a guy who can see and interact with spirits, ends up living with a hot ghost. Stereotypical enough? Well, throw in a whole inn full of hot non-humans/super-humans, all of whom are living with our protagonist. Sounds like something straight out of To Love-ru or Monster Musume, right? Honestly, you wouldn't be wrong with that comparison, although this one is a little different. While there are some decent arcs, most of them are just about pushing up the female characters' affection points.
There is no overall/central story to speak of, but the individual episodic story arcs are dealt with fairly well. The pacing is decent and there haven't been any major plot holes or the like so far.
This manga resembles Love Hina or Bokura wa Minna Kawaisou rather than the aforementioned titles. If you liked either of these titles, then you might like this manga as well.

Art (8/10):
I initially mistook the artwork for the work of Tosh (Shun Saeki), of Shokugeki no Souma fame, but it proved wrong. Only later did I realize that the resemblance was because Tosh was an assistant of Tadahiro Miura, the author of this one.
Anyhow, the artwork in Yuragi sou no Yuuna san is brilliant, with every detail being carefully drawn. The character art in particular, is top notch.

Character (5/10):
The main character in this manga is pretty decent, for a harem protagonist. He gets stuff done, is pretty powerful, isn't thickheaded and of course, is hilarious (unwillingly, most of the time). There isn't much more that I could ask of a protagonist... but the problem lies with the other characters.
All the other characters follow the common archetypes. There's the clumsy girl, the nosy-but-well-meaning classmate, the always-drunk older girl, the 'how shameless!' girl (you know what I mean), the cat-girl and the secretly-dangerous older-than-she-looks loli. They all get some small amount of development, with individual character arcs, but it hasn't really been sufficient to set them apart from their corresponding archetypal images.

Enjoyment (6/10):
It was enjoyable for the most part, and was a fairly quick read. I wouldn't call it exceptional by any means, but I wouldn't call it unreadable either.

Overall (6.25 ~ 6/10):
Altogether, Yuragi sou no Yuuna san is a decent manga, which manages to be fairly interesting, even with its ecchi and harem elements. Though there are some scenes which bear resemblance to To Love-ru, it is still fairly readable in its own right.